THE SURFACE-TENSION OF COPPER-NICKEL-ALLOYS

The surface tension of copper-nickel alloys was measured, both as func tions of concentration and temperature, using electromagnetic levitati on and the oscillating drop technique. The measurements covered the en tire concentration range from c(Cu) = 0 to 100%, and a temperature ran ge that included the molten as well as the undercooled regime. The res ults agree well with a model based on Butler's formula for the surface tension and chemical potentials measured in the bulk liquid phase. Th is allows one to calculate the surface segregation of this system.